50 results about "Logarithmic spiral" patented technology

The invention relates to the technical field of tunnel engineering construction, in particular to a long tunnel full-section construction circulating footage optimization system and method. Aiming at the problems of inaccurate support force calculation and lack of a comprehensive evaluation system in the prior art, the method comprises the following steps of: setting multi-grade circulating footage in a test section, calculating average time consumption per linear meter and single-cycle error time under each grade, and counting the optimal candidate footage of the whole construction period according to the calculated time consumption and single-cycle error time; establishing a tunnel face stability failure model, and determining the maximum load of the surrounding rock of the tunnel face; a logarithmic spiral failure model of the tunnel face is established, and the corresponding relation between the multi-gear circulating footage and the supporting force is obtained; establishing a cyclic footage evaluation index according to the construction period and the supporting force of the multi-gear cyclic footage, calculating a comprehensive score of different cyclic footage according to the cyclic footage evaluation index, and screening an optimal footage; and rechecking the optimal footage by taking the construction aging average value of the optimal candidate footage of the test section and the maximum load of the surrounding rock of the tunnel face as comprehensive evaluation indexes.

The invention provides an end face logarithmic spiral oscillating tooth transmission device with an adjustable backlash. The device comprises a transmission assembly. The shell allows the movable teeth to pass through; the lubricating assembly comprises an elastic telescopic piece and an abutting assembly, the elastic telescopic piece is arranged in the lubricating hole and can abut against the hole wall of the lubricating hole, one end of the abutting assembly is connected with the end of the elastic telescopic piece, the other end of the abutting assembly abuts against the shell, and the face, abutting against the shell, of the other end of the abutting assembly is an inclined face; wherein the area where the movable teeth rotate in the circumferential direction comprises a top area and a bottom area, and when the movable teeth drive the lubricating assembly to rotate in the bottom area, the lubricating assembly recovers deformation and extends so as to push the abutting assembly to get close to the inclined face, and a space is released for lubricating oil to enter the lubricating hole; when the movable teeth drive the lubricating assembly to rotate in the top area, the lubricating assembly is compressed by the inclined face, so that the elastic telescopic piece is shortened, and the abutting assembly moves into the lubricating hole to extrude lubricating oil in the lubricating hole and discharge the lubricating oil to the meshing tooth face of the inner gear ring.

The invention provides a logarithmic spiral motor design method, belongs to the technical field of spiral motor design, and designs logarithmic spiral electromagnetic topology, fuses a plurality of materials, constructs an integrated structure body, and sets an intelligent regulation and dynamic matching control mode. Firstly, a magnetic flux path is optimized, magnetic flux is naturally distributed in the tangential direction of a spiral line by utilizing the characteristic that the curvature of the spiral line is continuously increased or decreased, edge magnetic flux distortion is reduced, then near-field coupling is enhanced, and the magnetic flux superposition phase difference between adjacent spiral units is controlled by adjusting spiral line parameters. The double targets of active enhancement of effective magnetic flux and suppression of magnetic leakage are achieved. Through deep fusion of geometric characteristics and electromagnetic laws of logarithmic spiral lines, pole slot limitation and loss bottlenecks of a traditional motor are broken through, through a logarithmic spiral line electromagnetic topology design normal form, geometric curvature and magnetic field distribution are quantitatively associated, and through a conductive, magnetic conductive and heat dissipation composite winding and an intelligent magnetic barrier structure, multi-field collaborative optimization is achieved.

The application discloses a method for determining support pressure of a tunnel face in opposite excavation, and comprises the following steps: S1, establishing an active failure mode of a soil body of the tunnel face in opposite excavation, wherein the active failure mode comprises a logarithmic spiral wedge-shaped sliding surface failure body in front of two tunnel faces and a semi-elliptical collapse body above and in front of the two tunnel faces; S2, obtaining a moment balance equation of the logarithmic spiral wedge-shaped sliding surface failure body and the semi-elliptical collapse body based on a limit equilibrium method; and S3, reversely deducing a critical support force P of the tunnel face in opposite excavation according to the moment balance equation. The active failure mode and the critical support force P obtained by calculation are reliable and reasonable.

The one-way clutch comprises an outer ring and an inner ring which are concentrically arranged, and a rolling body is arranged between the outer wall of the inner ring and the inner wall of the outer ring; a plurality of curved-surface grooves are uniformly formed in the outer wall of the inner ring, and the rolling bodies are arranged in the curved-surface grooves; the curved surface groove is not a regular arc groove and comprises a separation groove section and a meshing groove section which are connected with each other, the separation groove section is an arc groove, the meshing groove section comprises an oblique line section and a logarithmic spiral curve section, and the oblique line section is transited to the logarithmic spiral curve section. The device is simple in structure, free of a rolling body supporting structure and a spring in the prior art, convenient to install and maintain and low in manufacturing cost.

This invention discloses a method for tooth profile modification and modeling of a logarithmic spiral live gear transmission, belonging to the field of mechanical transmission technology. The method includes: modifying the tooth profile of the moving tooth tip using circular arc curves or higher-order polynomial curves to obtain a modified moving tooth profile; modifying the profiles of the long axis transition section and the short axis transition section of the cam using higher-order polynomial curves to obtain a modified cam theoretical profile; obtaining the modified internal gear profile based on the motion mapping relationship between the modified moving tooth and the cam; establishing a static balance model to analyze the influence of modification parameters on contact force under working conditions; and establishing a three-dimensional model of the logarithmic spiral live gear transmission. This invention can significantly improve meshing accuracy and transmission smoothness, improve tooth profile contact stress distribution, enhance load-bearing capacity and fatigue resistance, and also provide feasible parameter guidance for actual production.

The application discloses a method for determining support pressure of a tunnel face in opposite excavation, and comprises the following steps: S1, establishing an active failure mode of a soil body of the tunnel face in opposite excavation, wherein the active failure mode comprises a logarithmic spiral wedge-shaped sliding surface failure body in front of two tunnel faces and a columnar collapse body above the two tunnel faces; S2, determining a geometric relationship of the active failure mode, and obtaining a moment balance equation of the logarithmic spiral wedge-shaped sliding surface failure body and the columnar collapse body based on a limit equilibrium method; and S3, reversely deducing and calculating a critical support force P of the tunnel face in opposite excavation according to the moment balance equation. The active failure mode and the critical support force P obtained by calculation are reliable and reasonable.

The invention discloses a holding type variable-curvature gripper based on a logarithmic spiral curve and an operation method of the holding type variable-curvature gripper. The cable-embracing type variable-curvature gripper comprises a variable-curvature gripping arm and a driving rope. When the variable-curvature grabbing arm grabs an object, the variable-curvature grabbing arm is pulled by the driving rope to be bent in the direction of the grabbed object, the grabbed object is pushed, and by means of the gradually-increased bending curvature of the variable-curvature grabbing arm, the front end of the variable-curvature grabbing arm is curled to catch the object, and the grabbed object is gradually bound to the position with the moderate curvature. Grabbing force closing is formed at the contact point of the variable-curvature gripper and the grabbed object through the pulling force of the driving rope, and enveloping of the grabbed object is achieved. The mechanical arm is composed of a rigid structure, a variable-curvature holding type grabbing mode based on the logarithmic spiral curve is adopted, the mechanical arm has the advantages of being high in grabbing stability, adaptability and accuracy and low in structure control complexity, and objects of different sizes and shapes can be grabbed.

The embodiment of the invention provides a leg spiral self-adaptive binding device adaptive to a human body and a robot and wearable equipment. The binding device comprises a driving unit, a binding unit and a control unit, the spiral binding unit is in transmission connection with the driving unit, and the spiral binding unit comprises spiral binding elements which are distributed in the circumferential direction of the leg and symmetrically arranged in the length direction of the leg in a logarithmic spiral track mode; the Bowden cable group is arranged between two adjacent spiral binding elements and between the driving unit and the spiral binding elements in a penetrating manner; the pressure sensing assembly is arranged on the side, close to the leg, of the spiral binding unit; wherein the driving unit is used for driving and adjusting the winding and unwinding of the Bowden wire group according to the contact pressure between the spiral binding unit and the legs, which is detected by the pressure sensing assembly, so as to adjust the bending radian and the tightness of the spiral binding unit.

A wind power collection device, a gas storage device, and a power generation system, where the wind power collection device includes an impeller, an outer side wall of the impeller is composed of four mutually spliced flow guide surfaces, radial cross sections of the four mutually spliced flow guide surfaces correspond to four mutually spliced flow guide curves, the flow guide surfaces are formed by rotating and stretching the flow guide curves around an axis line of the impeller in an axial direction; and the flow guide curves include a segment of convex first logarithmic spiral line and a segment of concave second logarithmic spiral line, and the first logarithmic spiral line and the second logarithmic spiral line of the flow guide curves are smoothly and transitionally connected at one side close to the axis line.

The invention discloses a multi-mode sensing gripping device and method based on a variable rigidity logarithmic spiral configuration, and is characterized in that the device comprises a driving module and a plurality of gripping blocks which are sequentially arranged along a logarithmic spiral, and the adjacent gripping blocks are hinged; wherein each grasping block comprises a skeleton main body outer layer, a variable rigidity middle layer and a buffer inner layer; wherein the skeleton main body outer layer is used for providing device support and appearance deformation; the variable rigidity middle layer is used for realizing local rigidity adjustment; a multi-modal sensor module for collecting multi-modal grasping data of the grasping block is distributed on the grasping block; and the driving module is connected with each grasping block. Through organic combination of a logarithmic spiral configuration and a variable rigidity material, and meanwhile, a flexible touch sensor array is arranged on the inner layer of the grabbing device, so that real-time detection and cooperative adjustment of rigidity, form and force control in the grabbing process are realized.

The application relates to the technical field of range hoods, and provides a volute, a centrifugal fan and a range hood. The profile of the volute comprises first, second, third and fourth profile segments connected in sequence, and the two profile segments connected in sequence are smoothly connected. The third profile segment constitutes the main body of the volute, the second profile segment constitutes the volute tongue of the volute, and the third profile segment is located on a logarithmic spiral curve. Since the logarithmic spiral curve where the third profile segment is located is an arc segment generated with the same center, the curvature of the third profile segment is continuous, and the radial gap between the logarithmic spiral curve and the reference circle is gradually increased through the design of the reference circle. Therefore, the change of the polar radius of the third profile segment is continuous, the error of the profile of the volute is reduced, the vortex in the volute can be prevented to reduce the noise of the volute, the gas in the volute can be more concentrated, and the smoke exhaust efficiency of the volute is improved.

The invention discloses an inner support type foundation pit supporting soil pressure calculation method based on an asymmetric soil arching effect, and relates to the technical field of geotechnical engineering.The method comprises the steps that S1, a sliding surface model described in a logarithmic spiral shape is established, a soil body behind a supporting structure is divided into an upper area influenced by the soil arching effect and a lower area not influenced by the soil arching effect, and the upper area is divided into a sliding surface model; s2, introducing an asymmetric soil arch calculation model considering principal stress deflection in the upper region, constructing an arch differential unit along a large principal stress track, and analyzing a soil stress state based on a stress Moire circle, S3, respectively carrying out stress analysis on the differential units in the upper region and the lower region, solving soil pressure distribution of the support structure, and calculating the soil pressure distribution of the support structure. S4, calculating resultant force of soil pressure borne by the supporting structure and the position of an action point of the resultant force; according to the method for calculating the supporting soil pressure of the inner supporting type foundation pit under the asymmetric soil arching effect, a scientific theoretical basis and a practical engineering method are provided for design of a foundation pit supporting structure under a soft foundation and a complex environment.

The present invention relates to a door stopper which incorporates an automatic height adjustment mechanism so as to be adapted to the state of a bottom surface (height difference) on which a door is installed, and minimizes the influence due to an installation error and is easy to use. The door stopper comprises a fixed bracket fixed to the door, and a multi-leg support portion including at least two rods having different lengths, which are coupled to the fixed bracket in a hinged manner, or a cam-type support portion having the logarithmic spiral outer circumference coming into contact with the bottom surface with rotational radius varying depending on the angle of rotation.

The present application relates to the technical field of centrifugal fans and discloses a volute for a centrifugal fan, comprising a volute top plate, a volute enclosure, and a volute bottom plate. The volute enclosure is connected between the volute top plate and the volute bottom plate. The cross-sectional outer peripheral profile of the volute enclosure includes a logarithmic spiral diffusion profile, a logarithmic spiral profile, a volute tongue profile, and a volute tongue diffusion profile that are smoothly connected in counterclockwise order. The logarithmic spiral diffusion profile is a straight line, the logarithmic spiral profile is a gradually expanding spiral profile, the volute tongue profile is a curve, and the volute tongue diffusion profile is a straight line. Air has better flow characteristics within the volute, improving efficiency and reducing noise.

This invention discloses a pseudo-static calculation method, system, storage medium, and electronic device for active earth pressure in finite-width fill under seismic conditions using the RB displacement mode. The method first determines the failure mode based on the fill geometry, identifying a potential slip surface composed of a combination of logarithmic spirals and straight lines. The core innovation lies in establishing a small principal stress trace arch model to quantitatively analyze the deflection of principal stresses in the soil caused by friction at the wall-soil and rock-soil interfaces, and deriving the lateral earth pressure correction coefficient. K w Based on this, the damaged soil is divided into zones, and differential equations considering the equilibrium of seismic inertial force, self-weight, and interface forces are established, combined with the aforementioned correction coefficients. K w By performing the solution, a more realistic distribution of earth pressure intensity, magnitude of resultant force, and location of application point are obtained. This invention overcomes the limitations of traditional semi-infinite soil theory and provides an accurate and reliable theoretical tool for the seismic design and stability analysis of retaining structures in narrow spaces.

The application discloses an electrocardiosignal denoising method using an improved WOA-VMD algorithm and belongs to the field of electrocardiosignal processing. The application introduces a perception disturbance mechanism into WOA by using the characteristics of VMD based on complete non-recursive decomposition, and replaces the classical logarithmic spiral curve with an equal-pitch Archimedean spiral curve to optimize the mode number and penalty parameter in VMD. Then, the ECG signal is decomposed by VMD to obtain a series of IMF components, the noise components are determined by a correlation coefficient, and the improved wavelet threshold denoising is performed on the noise components. Finally, the components are reconstructed to obtain the denoised signal. The comparison experiment of the method with the wavelet threshold algorithm and the VMD algorithm shows that the method can effectively remove various interferences in the electrocardiosignal, better retains the waveform characteristics of the ECG signal, and has potential clinical guiding significance.

An augmented logarithmic spiral antenna structure includes a first conductive layer, a dielectric layer and a second conductive layer. The first conductive layer includes a first spiral arm and a plurality of second spiral arms. The first spiral arm includes a first initial radius. The second spiral arms are disposed around and connected to the first spiral arm, and each of the second spiral arms includes a second initial radius. The dielectric layer has a top surface and a bottom surface, and the top surface is connected to the first conductive layer. The second conductive layer is connected to the bottom surface. A plurality of the second initial radii of the second spiral arms are different from each other, and different from the first initial radius.

The invention provides a pump, the pump comprising: a housing defining an interior volume; an impeller disposed in the interior volume of the housing, where the impeller includes a magnetic element, and at least a portion of a surface of the impeller conforms to a substantially logarithmic spiral; and a drive element adapted to magnetically couple with the magnetic element of the impeller.

A locking system for a vertical cable shuttle is disclosed. The locking system comprises a housing defining a guide path and slideably attached to a guide member. A braking lever configured to engage the guide member. The braking lever comprises a shock absorber fabricated along the braking lever and configured to absorb shocks during a fall. Further, a braking configured independent from the braking lever. The braking element is a logarithmic spiral structure configured to rotate into engagement with the guide member during the fall, and defines a constant slope angle for gripping of the guide member. The braking element having a braking surface to provide contact surface area with the guide member during the fall.

The centrifugal pump with double helical blades and the roller granulator using the same adopt double helical blades, the first blade and the second blade affect and balance each other; the profile line of the working surface of the first blade is an Archimedes spiral line, the profile line of the back surface of the second blade is a logarithmic spiral line; the profile line of the back surface of the first blade includes a part of the first constant-pitch spiral line close to the inlet side and a part of the first variable-pitch spiral line away from the inlet side, and the profile line of the working surface of the second blade includes a part of the second variable-pitch spiral line close to the inlet side and a part of the second constant-pitch spiral line away from the inlet side, which can optimize the instability of the fluid in the helical blade pump, reduce the occurrence of vibration and noise, and the second blade in the application is equivalent to the supplement of the first blade, effectively reduces the occurrence of cavitation and cavitation, and improves the hydraulic efficiency and stability of the centrifugal pump to a certain extent.

The invention discloses a circuit breaker opening and closing coil intelligent detection method and device, relates to the technical field of circuit breaker detection, adopts a composite machine learning model to construct an intelligent detection model, can identify weaker and more complex early fault features, improves the detection accuracy and sensitivity, and improves the detection accuracy. And then training an intelligent detection model by adopting a logarithmic spiral exploration strategy, a vortex path exploration strategy based on information entropy and a fractional order balance exploration strategy based on a damping sawtooth wave oscillation factor, so that the algorithm can be effectively prevented from falling into local optimum, and when facing data of circuit breakers of different models and different working conditions, the algorithm can be accurately detected. The training of the intelligent detection model can be effectively realized, so that the intelligent detection accuracy of the opening and closing coil of the circuit breaker is ensured.

An adding system for fire-extinguishing units is disclosed for producing a mixture of extinguishing agent and extinguishing agent additive (premix) by adding an extinguishing agent additive, e.g., a foaming agent, to an extinguishing agent, e.g., water, the adding system comprising a motor, which can be driven by the extinguishing agent stream, an adding pump, which can be driven by the motor, an adding line, and an extinguishing agent additive line. The invention increases the operational reliability of an adding system for fire-extinguishing units by the outer wall of the working chamber of the motor being in the form of a rotation motor, which can also have the shape of a logarithmic spiral. Furthermore, the wall of the drainage housing of the motor, which is in the form of a rotation motor, can have a through-slot for letting the extinguishing agent in and / or out. Moreover, the inlet of the adding pump can be arranged such that the extinguishing agent additive can flow into the adding pump substantially parallel to the movement direction of the pistons of the adding pump. Finally, the adding pump can have an integrated relief valve.

The application relates to the field of information technology, in particular to an in-ear earphone acoustic cavity optimization design method based on a bionic cochlea structure, which comprises the following steps: carrying out finite element analysis on the acoustic cavity geometric model, calculating the propagation path and pressure distribution of sound waves in the cavity, and judging whether the sound waves form standing waves in a predetermined frequency range; if the finite element analysis result shows that standing waves exist, adjusting the spiral angle parameter of the logarithmic spiral model, recalculating the sound wave propagation characteristics in the model, and stopping until the standing wave phenomenon is suppressed; according to the optimized spiral taper structure model, combining the acoustic characteristics of the earphone driving unit, calculating the incidence angle of sound waves at the entrance, and judging whether the sound waves can enter the acoustic cavity efficiently; if the sound wave incidence angle exceeds the preset range, adjusting the entrance diameter parameter of the logarithmic spiral model, recalculating the sound wave incidence angle, and stopping until the matching requirement of the driving unit is met.

The invention relates to an axial foil bearing (61) having at least one spring foil and at least one top foil (44) which is provided with a stepped structure (8) in the circumferential direction for forming a loadable fluid film in a bearing gap, said stepped structure having at least three segment transitions (21, 22; 22, 23; 23, 24; 24, 25; 25, 26; 25, 21). In order to improve the axial foil bearing (61) with respect to maximum bearing capacity and / or reduction of friction loss during operation, the axial foil bearing (61) is formed in a section transition (21, 22; 22, 23; 23, 24; 24, 25; 25, 26; a step (31-36) having a logarithmic spiral step line (13) is formed on the top foil (44) in each case between two circumferentially adjacent sections of the first, second, third, fourth, fifth, sixth, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh, seventh,

A centrifugal disc for centrifugal spray forming, a plurality of liquid throwing grooves are arranged on the disc surface of the centrifugal disc in the circumferential direction, the center line of the liquid throwing groove is a logarithmic spiral line with the center of the disc surface as the center; a molten liquid cylinder is arranged at the center of the disc surface, the cylinder wall of the molten liquid cylinder is provided with liquid outlet holes communicated with each liquid throwing groove; a piston rod is arranged in the molten liquid cylinder, the piston rod can slide up and down, and is used for closing or opening the liquid outlet holes, so that the metal melt in the molten liquid cylinder is thrown out from the liquid outlet holes in intervals and quantitatively, and then the droplets with nearly consistent diameters are obtained. In addition, the liquid throwing groove can throw the droplets along the radial direction of the centrifugal disc to impact the deposition layer in the positive direction, so that the problem of the reflected droplets impacting the deposition layer again is solved from the source. Compared with the oblique impact, the positive impact in the radial direction is not only beneficial to improve the density of the fusion of the droplets and the deposition layer and form fine grain structure, but also the droplets can be almost completely fused on the deposition layer, so that the effective deposition rate of the metal material is greatly improved.

The utility model discloses a kind of flexible multi-dimensional ureteroscope under grabbing device based on logarithmic spiral structure, comprising: flexible grabbing head, it can be logarithmic spiral type bending to grab stone;Flexible body part passageway, with ureteroscope operation passageway adaptive setting, flexible grabbing head is connected in the first end of flexible body part passageway;Hand control operating part, including fixed part and movable operating part, fixed part is fixedly connected in the second end of flexible body part passageway, movable operating part is movably set in the second end of flexible body part passageway, movable operating part is used to drive flexible grabbing head bending as logarithmic spiral structure.The flexible grabbing head of the utility model can be bent in multiple dimensions, realize the grabbing task of each direction self-adapting size, and can complete not in the effective grabbing range of traditional equipment, narrow space or stone in incarceration, adhesion inconvenient handling condition under grabbing task, can be used for lithotomy task in multiple scenes.

The utility model relates to the technical field of butt welding elbows, in particular to a high-pressure-resistance butt welding elbow which comprises an elbow body, a plurality of flow guide fins are arranged on the inner side of the elbow body, a stress protection sleeve is arranged on the outer side of the elbow body, and a plurality of bionic reinforcing ribs are arranged on the inner side of the stress protection sleeve. The rib height h of the bionic reinforcing ribs and the reference wall thickness t0 of the elbow body meet the condition that h is equal to (0.1-0.15) t0, the ribs of the bionic reinforcing ribs are distributed according to logarithmic spiral lines, the trend of the bionic reinforcing ribs and the tangential direction of the center line of the elbow body form an included angle of 30-45 degrees, and the wall thickness of the elbow body is distributed in a sine square manner along the tangential angle theta of the center line. The flow guide fins are matched with the bionic reinforcing ribs distributed in a logarithmic spiral mode to form a composite flow guide field, the medium flow resistance is reduced by 15%-20%, vortex generation is effectively restrained, the tangential included angle design of the ribs is 30-45 degrees, fluid shear force and the trend of the reinforcing ribs form optimal mechanical coupling, and turbulent flow energy loss is reduced.

A laser chamber includes a guide portion arranged therein such that at least a part of a first guide surface extends between first and second virtual curves over a first section of first and second virtual logarithmic spirals. The first virtual curve has a curvature decreasing along a flow direction and is a virtual curve from a first phase angle to a second phase angle of the first virtual logarithmic spiral in which an angle at which a straight line from an origin and a tangent of the first virtual curve intersect is 103°. The second virtual curve has a curvature decreasing along the flow direction and is a virtual curve from the first phase angle to the second phase angle of the second virtual logarithmic spiral in which an angle at which a straight line from the origin and a tangent of the second virtual curve intersect is 96°.